Spray Foam Insulation R Values Per Inch

Open cell spray foam has an r value of about r 3 7 per inch while closed cell spray foam has an r value that may be as high as r 6 5 per inch.

Spray foam insulation r values per inch.

If you want to install spray foam in a stud wall and price is no object then it would seem to make sense to specify closed cell spray foam right. In comparison an inch of blown fiberglass insulation has an r value of 3 1 3 4 and an inch of blown cellulose in an attic has an r value of 3 2 3 7. Closed cell spray foam insulation. Walls below grade and above grade.

Considering diy blown fiberglass insulation vs spray foam both require care to get the thickness right. Closed cell foam r values spray with an r value of 3 5 per inch per inch of thickness. The r value of fiberglass insulation is approximately 2 2 per inch so much thicker fiberglass insulation is required to achieve the same r value of 38. The closed cell spray foam stops air infiltration and provides about an r 5 per inch.

R values are additive so you can multiple the number of inches of insulation thickness times the r value to arrive at a total insulation value. Eco spray foam insulation. The r value of. Varies widely but filling a 2 4 cavity to r 13 with closed cell spray foam costs about 3 50 to 5 25 per sq.

That means if you used foam it green closed cell which is r 7 per inch it s r value for a 3 5 deep wall. Spray foam insulation vs fiberglass r value is about equal for open cell insulation and about double for closed cell insulation per one inch layer. Insulate rim joists and other large areas with this product meant for big jobs. Comparing fiberglass to foam fiberglass is the less expensive choice for wall insulation and is the spray foam insulation rental industrial spray foam insulation jun 12 2017 focusing on spray foam insulation materials there is a difference.

Open cell foam insulation values r3 r4. Made with plant based products such as soy eco spray foam is more eco friendly. Why spray foam insulation is so effective in meeting code requirements is that it has a higher r value per inch of product used than batts. The r value of spray foam insulation is approximately 6 per inch so those using spray foam as their insulator will need about 6 3 inches of thickness to reach r 38.

For example a wall with 3 fiberglass batting r value of 10 8. For example closed cell spray foam depending on brand can offer an r 6 or r 7 per inch. And roofs closed cell spray foams provide a higher r value per inch than less expensive insulation types like fiberglass cellulose or open cell foam. The r value is r 3 5 to r 3 6 per inch so filling a 2 4 cavity yields about an r 13.

Closed cell spray foam has a far better r value per inch than other less effective insulations like cellulose fiberglass or even open cell foam. Open cell spray foams are between 5 and 1 lbs per cubic foot and have an r value of 3 0 4 0 per inch of insulation.